Southampton - Frank Lampard insisted Chelsea are not the finished article yet after Tammy Abraham and Mason Mount celebrated their England call-ups by inspiring a 4-1 rout of struggling Southampton on Sunday.

Abraham, Mount and their Blues team-mate Fikayo Tomori were all named by England manager Gareth Southgate in the squad for the forthcoming Euro 2020 qualifiers in the Czech Republic and Bulgaria.

The promising young trio hogged the spotlight once again at St Mary's as Abraham and Mount netted to maintain their superb starts to the season.

Chelsea are up to fifth in the Premier League heading into what promises to be a memorable international break for the club's three young talents.

"I am happy we are in and around the top group. Obviously Liverpool are out on their own at the minute, but at this early stage we are in a nice position," Lampard said.

"This should give us determination to go away (for international duty) and come back in the same vein because the minute you relax in this league it can all change very quickly."

Abraham has nine goals in all competitions for Chelsea this term, underlining why Southgate is keen to get him action in a competitive match to ensure he commits to England.

The 22-year-old striker has won two caps for England in friendlies against Brazil and Germany in 2017, but he had flirted with switching his international allegiance to Nigeria, who he qualifies for through his father.

Mount, 20, bagged Chelsea's second goal to once again showcase the predatory instincts that have helped the midfielder make a smooth transition to the Premier League following last season's loan alongside Tomori at Derby.

Danny Ings got one back for Southampton, but N'Golo Kante and Michy Batshuayi struck to make it four successive wins in all competitions for Chelsea, who are beginning to thrive in Lampard's first season in charge.

But Lampard believes Chelsea can get even better, especially at the back.

"We can't afford to give little moments (to the opposition). That is a pointer for all of us that we are not there, we are nowhere near the finished article," he said.

"We are a few points short of where we should be, based on our performances and that is not bad luck, just me being self-critical, but I'm pretty happy."

Callum Hudson-Odoi was starting for Chelsea for the first time in the league this season and the England winger created their first chance with a burst that ended with Abraham shooting straight at Angus Gunn.

It was a warning that Southampton failed to heed as Chelsea took the lead in the 17th minute.

Hudson-Odoi floated a long pass towards Abraham and he nipped ahead of Saints defender Maya Yoshida to reach it on the edge of the area.

With Gunn having sprinted off his line, Abraham lofted his shot high over the keeper and the ball crossed the line despite Yoshida's despairing attempt to clear with a bicycle kick.